260 Transactions. — Zoology. 



I have seen similar larvae in other localities, but have been 

 unable to keep them. Like B. luvdnosa, the Ccroplatus larva 

 forms a glutinous web in crannies of the log under which it 

 lives, and in this web it habitually lives. It seems unable to 

 crawl on any hard surface, but remains suspended in its web, 

 and wheii it moves it enlarges the web first. These larvae are 

 not luminous, in this respect differing from the larvae of C. 

 mastersi, Sk. The exact function of the glutinous web I can 

 do no more than guess at. It may, as mentioned above, assist 

 in locomotion ; it may enable the suspended larva to keep out 

 of the reach of enemies such as planarian worms or preda- 

 ceous insects. A diagram of the digestive organs of a Myceto- 

 philid in Theobald's " British Flies " shows extremely large 

 salivary glands, and he remarks that these glands usually 

 extend the whole length of the body ; the glutinous material 

 is probably secreted by them. The pupa of both B. luviinosa 

 and C. dendyi is suspended in the web formed by the larva. 



About eight hundred species of Myceto'philidcB are at 

 present known. Many of the genera appear to be almost 

 cosmopolitan. All the largest genera of Europe are repre- 

 sented in New Zealand. Judging from the very varied types 



1 have already collected, I should think that New Zealand 

 will prove to be far richer in species than Australia, for, though 

 the number of species described by Skuse in all probability 

 represent but a small proportion of the total number, those 

 described are confined to comparatively few of the sub- 

 sections. 



IMAGO. 



External Structure. 



The head is narrower than the thorax, round or oblong or 

 flattened hemispherical on the fore part, situated deep in the 

 thorax. Front of both sexes broad. Eyes round or oval, 

 frequently emarginate on the inner side or renifoi'm, set with 

 short hair. Ocelli three, or only two : in the former case 

 they are either disposed in a triangle, in a bent or sometimes 

 a straight line on the front, or two are situated one on the 

 border of each of the compound eyes, and the third placed in 

 the middle of the anterior border of the front ; in the other 

 case, always at the inner border of each of the compound 

 eyes. Proboscis short, retired, rarely elongate or beak- 

 shaped. Palpi three- or foiu'-jointed, prominent, generally 

 incurved, the first joint always very small. Antennae gene- 

 rally arcuated, straight, or diverging sideways, 2+10 to 



2 + 15 jointed ; the joints of the scapus distinctly set off ; 

 flagellar joints pubescent, sometimes verticillate - setose. 

 Thorax ovate, more or less arched. Prothorax with close 

 short pubescence, sometimes with longer hair, perhaps mixed 



